Core sampling arrangement for operation inside geological layers



Jan. 16, 1962 B. P. BERTHELIN 3,

CORE SAMPLING ARRANGEMENT FOR OPERATION INSIDE GEOLOGICAL LAYERS FiledMay 20, 1958 sates it.

Patented .lan. id, 19 32 3,ill6 959 CGRE SAMPLING ARRAfQGERiiENT FGlrlGPERA- Titlhl 1N Sillll GEQLOGEQAL LAYERS Bruno Pierre Berthelin, Paris,France, assignor to Susi-etc tie i rospection Elcet'rigue, ProeetlestSchlumherger,

Paris, France, a corporation of France Filed May 29, 1953, Ser. No.736,626 4 Claims. (til. 175-4) My invention has for its objectimprovements in coresampling arrangements for operation in geologicalstrata and, more particularly although not exclusively, in the sidewalls of bore holes.

It is a well-known fact that certain apparatus providing forcore-sampling in geological layers lire hollow tubular missiles whichare urged into the layers by a sort of gun which is brought into theimmediate proximity of the layer from which a core is to be removed, thetubular missile being connected with the gun through a retaining cable.When the missiles are urged into layers, they engage and cut out of thelatter the de sired sample which is thereafter carried inside thetubular missile. When the gun is moved, it carries along with it throughthe agency of the cable the missile carrying the sample, the missilebeing finally returned to ground level, where it is an easy matter toremove the sample and to examine it.

It is an object of the invention to provide an improvement in the meansconnecting the cable with the missile forming the core-sampling tool.

To this end, there is provided a connection between the missile and thegun by means of a single cable secured at each end to the gun andpassing through slots formed in the tubular core-sampling tool ormissile, said cable being carried as it passes through the missile by amember adapted to be crushed or collapsed so that, at the moment of thefiring of the missile and subsequently, the sudden stress exerted on thecable may be damped or reduced to prevent any breaking of the latter.

Further objects and features of my invention will appear in the readingof the following description, reference being made to the accompanyingdrawing illustrating diagrammatically by way of example and by no meansin a limiting sense a preferred embodiment of my invention. The singlefigure of the accompanying drawing is a horizontal cross-section of acore-sampling apparatus operating with a charge of gunpowder inside abore hole and incorporating the principle of my invention.

In said figure, 1 designates a gunshaped section of a core-samplingapparatus lying inside the bore-hole 2 and adapted, as well known perse, to project transversely of the bore-hole a succession ofcore-sampling tools or missiles into the side wall of said bore-holewith a view to removing samples therefrom. The cross-section illustratedpasses through one of the core-sampling tools or missiles.

Generally and as well known per se, a plurality of core-sampling toolsare arranged at different levels and in superposed formation inside thebody of the apparatus. The actual core-sampling tool is constituted by atubular member 3 closed at its rear end by a socket 4 behind which isprovided inside the gun-shaped section 1 a charge of gun-powder 5adapted when fired in any known or suitable manner to project the toolinto the ground.

According to my invention, the core-sampling tool is provided in itsside wall with lateral slots 6 which serve, on the one hand, for thefree flow of the borehole liquid out of the tubular member 3 when thetool enters the geological stratum to be examined, said slots serving onthe other hand as a transverse passage for th tool-retaining cable '7which is Wound and secured in a conventional manner through its ends 8and 3 inside corresponding recesses formed in the body of thecore-sampling apparatus. Said cable passes through a copper tube whichhas received previously the shape of a broad U, as illustrated, andwhich passes through a disc or plate 10 fitted inside the core-samplingtool 3, said disc being secured to the outer end of a tubular sleeve 11made of a suitable synthetic resin, such as that sold under the name ofBakelite for instance, and housed coaxially inside the tubular sectionof the missile tube 3.

The arrangement described operates as follows: when the gun has beenfired and under the action of inertia, the cable 7 has a tendency tohold back the missile so that the sleeve 1:. collapses slightly underthe'action of the section of the cable passing through the core-samplingmissile and when the latter has entered the side wall of the bore-hole,as illustrated in dotted lines in the drawing, the copper tube 9 engagesthe rear ends 12 and 12 of the slots d closed by the socket l. By reasonof the presence of the shock-damping means including the collapsiblesleeve 11, there is no risk of the cable '7 breaking. The core-samplingtool is removed simply by drawing outwardly and upwardly the body of theapparatus 1 through action on the main cable supporting the apparatus,the cable '7 remaining attached to the apparatus carrying along with itthe missile enclosing the desired sample.

The arrangement according to the invention ensures furthermore theadvantage consisting in that, during the removal of the apparatus andits raising up to ground level, the cable 7 engaging the rear section ofthe missile draws the latter along through its rear end, whichcondition, for certain samplings, is more favorable than the conditionaccording to which the missile is drawn along forwardly.

Obviously, many modifications may be brought to the arrangement, withoutunduly widening its scope as defined in the accompanying claims.

What i claim is:

l. in a core-sampling arrangement, the combination of at least onegun-shaped section including a charge-carrying chamber, a missile to beinserted in said section and including a tubular body open at its frontend and having a closed rear end which is adapted to be subjected to thefiring of the charge in the charge-carrying chamber, said body beingprovided in its side wall with two longitudinal slots on opposite sidesthereof extending rearwardly to a point adjacent the rear end of saidtubular body, a cable the ends of which are operatively connected to thegun-shaped section on each side of the missile therein and the medialportion of which passes through said missile slots and across theinterior of said tubular body or" the missile, and collapsible meanspositioned rearwardly within said tubular body and in front of and inlongitudinally spaced apart relation to the rear ends of said slots forsupporting that portion of said cable passing across the interior ofsaid tubular body, said means being capable of rearward collapse in adirection toward the rear ends of said slots to damp the thrust exertedon the cable upon firing of the missile.

2. In a core-sampling arrangement, the combination of at least onegun-shaped section including a chargecarrying chamber, a missile to beinserted in said section and including a tubular body open at its frontend and having a closed rear end which is adapted to be subjected to thefiring of the charge in the charge-carrying chamber, said body beingprovided in its side wall with two longitudinal slots on opposite sidesthereof extending rearwardly to a point adjacent the rear end of saidtubular body, a cable the ends of which are operatively con nected tothe gun-shaped section on each side of the missile therein and themedial portion of which passes amaeae as through the missile slots, acollapsible tubular membercarried by the rear end of the tubular bodyand extending forwardly inside the latter clearly beyond the rear endsof the slots and capable of collapse in'a direction towards the rear endof the slots, a transversely perforated cover carried by the front endof the collapsible member for supporting the medial section of the cablewithin the transverse perforation, the collapsible member being adaptedto damp the thrust exerted on the medial portion of the cable uponfiring of the missile by allowing said medial portion to recede intecontact with the rear ends of the slots.

3. The apparatus of claim 2 wherein said tubular member comprises afrangible material.

4. The apparatus of claim 2 further comprising a metallic sheathsurrounding said medial section of said cable.

Ser. No. 271,524, Schlumberger (A.P.C.), published May 25, 1943.

UNITED STATES PATENT OFFICE I CERTIFICATE OF CORRECTION Patent Nob 3 Ol6959 January l6 1962 Bruno Pierre Berthelin It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

In the heading to the printed specification between lines 7 and 8 insertthe following:

Claim priority application France June 24L 1957 Signed and sealed this8th day of May 1962 (SEAL) Attest:

ERNEST W. SWIDER Attesting Officer DAVID L. LADD Commissioner of Patents

